The massive computing effort necessary for this research is provided by a Debian GNU / Linux cluster of 1342 nodes called ATLAS. Using 10+ TB RAM, approximately 1.3 PB storage and a special network able to transfer almost 4 days worth of DVD movies each second, the cluster achieves a measured performance of 32.8 TFlops. This performance places the ATLAS Debian GNU / Linux supercomputer at 4th place in Germany, 11th in Europe and 34th worldwide, at a cost of EUR 1.8m (~ US$ 2.8m).

"Thomas Lange's FAI package is extremely useful for automatic deployment of Debian [GNU / Linux]. For example, without much tweaking and using only two hosts, we were able to reinstall the cluster in about 2.5 hours and were only limited by those two servers' network connection.", said Dr. Aulbert. Dr. Grunewald added, "FAI with its class model was a major breakthrough, in readability, functionality, and maintainability. There's no way back now."

Beyond FAI, there are other useful tools for massive scale installation, deployment and management of Debian GNU / Linux machines for various scenarios. "Debian features an extremely large set of packages, making it THE distro of choice for keeping us out of the hassle to package needed software ourselves", said Dr. Aulbert.

By using Debian GNU / Linux at its clusters, the Observational Relativity and Cosmology Research Group reduced the amount of work needed on the hardware and software infrastructure, compared to other scientific clusters running on other distributions, allowing them to focus on their objective of detecting gravitational waves.

One of the many special hardware components they have is the network from Woven Systems which is a hierarchical fully non-blocking network. The EFX 1000 core switch features 144 10 Gb/s CX4 ports and connects currently to 32 TRX100 edge switches which feature 48 1 Gb/s ports and 4x10 Gb/s uplinks, reaching 2880 Gb/s. Also their Sun Fire X4500 are directly connected to the core switch.

According to Dr. Grunewald, the Merlin Debian GNU / Linux Beowulf 180 nodes cluster (launched in 2002) initially ran on a rpm based distribution, but in 2004 migrated to Debian GNU / Linux after the rpm distro vendor changed its licensing model. The total computing power of the 360 CPU cores has been estimated to be more than 1.3 Tflops peak; the data storage capacity is about 20 TB mirrored.

The Morgane Debian GNU / Linux Beowulf cluster, consisting of 615 compute nodes, 15 storage nodes, and some head nodes, launched in December 2006. The total computing power of the 1230 CPU cores has been estimated to be more than 6 Tflops peak, the data storage capacity is about 100 TB.